Radio receiving system



'Ndv. 24 1925- 1562.877 W. G. ELLIS- RAmb RECEIVING SYSTEM Filed June 16 1922 Inveni'or William 6. Ellis a; wer W925? To till 'whom i t ma y concern)- 3 Be .it knownthat I, WIILIAM G. ELLIS, a (citizen, of the United Statesof America,

"ments in R dio'Receivin Systern's; -of-vvhi.ch thefollovving is aspeci catiojn."

"1o: l-jreceiving systems, but =1nore specifioally to thegnullor. mininnirnpoint of reception in {receiving circuits. employing loop orc'oil reterferen'ceatthis point. i

"accuracy of loop radio' direction finders. or

1 mum' point of reception: as an indicationof station 1 Some. of

' beginning page'326, andfa suggestedniethd of .kcolnpensating for the {so-called antenna'eife'ct appears in. Figure 52, on

mum, 'I- have found that the compensation v 1 they demands}v for accuracy now required of 551m navigators, or to permit"ofthedesirecl successful avoidance of interference at? re-' .,*'ceiving stations. employing loop receptors 1 on -the bearing'ofminimum signal reception. ,"Itis the purpose of my invention to further improve the compensation. oftheso-called f-anten'na effect and other'currents inquad- "plainedJ; V v p v7 Figures; 1 tov 5 mclusive show vanoujs loop reception currents, as hereinafter ex.

I .6is' a diagrammatic explanation of my. in

I wreceptoriofone or more'turns having tuning. j condenserC in serles, one' -term nal of which A mation filed. June 16, 19 22. seems. 569327.-

' and residentfiof- Philadelphia, county -off 5 Philadelphia, State offPennsylvanigfhave v inventedjcertain new anduseful Improve- My l invention -relatesgenerally to radio f'those'e'mployingf loop or' coiljreception; i y'A-nobject of my -invention-is to improve 15'? captors,- jtherebyfreducing'or eliminating in particular object is to improve the;

r idiQcompasses employingthe null or ininia the 'directionor bearing of. the transmitting I j i r 5 C to getcompletej balance or"compensation; s. V w the causes:for"blurred minima This resistance should be variable 'for .a'd in loopreceptors are discussedin the Jour zq nal of the j Franklin Institute, volume} 188,

page 338501? thatpub lication. While the 3 compensator suggested improves the j miniobtained is not sufficiently complete to meet. I I 1 C' to elements having. greater leakage path 1, radiocomp ass stations "furnishing bearings installations in the vicinity of metall icfstruc vso'orientated as to bring interfering stations 7 I the wave reradiatedgfroin metallic struc "of energy, and therefore phasfa greaterfde; v .c'rement'vthan the-[direct "'vvziu' re, and.it fisf,. 7 rature ,or otherwise dephased from the pure.

. adjustable resistance in; connection with. the; 100i. v 'reactiveelement also permits of-obtainin'g g f'Wa y's. offernploying-my invention, Figurell lbein g'thelusual andpneferred form. .Fig'. r V g r sented the detector, diagrammatically Di Referring to Figure'l', lrrepresentsa'loop V p i ,ing reactance L, which ouldbe the. proce dure in case the unbaIanceis-caused an is connected to grid- G of a'three-electrode inductive unsymmetrical, or unbalanced :f I vacuum tube detector .V and the other; ter- 'minal connected to filament 'F-of'thesame I i tube, the battery A, the: telephones ofrjother responsive device Tfthebattery B'andplate f It will. therefore be seen that thejfirst terminal is {connected to'a small element, hav-f 160' a 7 ngnegligiblecapacity to-ground while thefl 'y a second terminal is connected toa-number'of elements having substantial capacity to. f ground,flparticularly the." battery A;" which-fl in ordinary practice is aHthreef-cell; sixty ampere-hour; stora egbatteryf tThiscapfiqcity is represented: by .apin Fig. 6yand thek'pa st Y practice'has been to compensatejifor this-ca; w p acityL o .:by' introducingavariablei con-Q. denser O .in a connection-to ground, {and p 7 .adjlusting" its -cap'acityTto" that. of 0 gem; this capacity (his. notpure', as :every con;v denser has apha'seangle or resistance factor; "f Which maybe represented? by'R inTFighf, V V isthereforenecessary to introduceia reslstance' R in connection with condenser justingj purposea'. as moving the batteriesQR} and other elements,-and.other variablefconj ditions, will alter the values of G andaR j. r SWitch S permits of connecting the line i containing ,variable elements G, a f d R to f the desired terminal of condenser In addition to theunsymmetrical' or unbalanced condition which may arise from connecting one terminal. of'the condenser '7 to ground thanldo ,the connectionstoi'thej other terminal, it 'is 'apparen't that in loopf tures other influences introduce quadrature; current effects in the. system. Forginstance,

tures naturally has encountered some loss evident that tWo waves, having dissimilar envelopes do not balanceof'themselvesk'. Thef 1 an adjustment for: this condition of affairs In Figs. 2. to inclusive,.I have repr'e' Fig: '2 shows the resistance elementju's'ed 05 in connection'with aninductivecoinpensatg grounding through the detector f 11 10.

Fig. 3 shows the resistance element directly in the loop, with switch S arranged to permit of inverting the detector connee: tions. This is the preferred arrangement when correcting an unbalance mainly due to reradiation, hereinbet'ore described Fig. d shows the compensating resistance element in parallel with the compensating reactance element. The 'rezictance element may be either capacity or inductance.

Fig.6 shows the compensiiting resistance element employed in connection. with the so-called compensating transformerrepresented by T, arrangement.

lVhile I have illustrated the usual and preferred form of employing my invention, and a number of modifications thereof, 1 do not wish to belimited thereby, as other modifications will vhe r adily apparent to. those skilled in the art. V

'Havingfully described my; invention, What I desire to secure by LettersPa-tent is:

1. In aradio receiving system the COHLblIlELw tion of a loop or receptor, a tuning element therein, a detector connected to points oi different potential of said tuning element, said detector being of a nature to create unbalanced electrical paths to ground'from said points, and a compensating circuit ineluding a resistance to compensate for said unbalanced grounding.

2 In a radio receiving system the combinationof a loop receptor, a tuning element therein, a detector connected to points of different potential of said tuning element, said detector being of a nature to create unbalanced electrical paths to ground from said points, and compensating circuit including a resistance and a reactance ele ment to compensate for said unbalanced grounding.

A radio receiving system including-a 1500p receptor a tuning element .in said loop, a detector connected: to opposite sides of said element, said detector being of a nature to create unbalanced electrical paths to ground fronisaidopposite connections, and a compensating circuit includinga resistance connecting one of said sides to; ground.

A radio receiving system. including a loop receptora tuning element in said loop, at detector connected to opposite sides of said element, said detector being of a nature to create imbalanced electrical paths to ground from said opposite connections, and a compensating circuit including a resistance and a reactance element connectingone: of said sides to; ground.

'WILLIAM G. ELLIS. 

